I've made some progress, managed to test my abs ecu on a ph1 Spider TS, and was able to connect to it, and activate the hydraulic circuit drain. So, my 'unrepairable' abs ecu from my ph2 V6 is working on a ph1 Spider TS.
Now, why can't I connect to it on the ph2 V6?
On the ph1 spider I'm using a 3-pin adapter on a switchable kkl set to 7, and providing a live feed straight from the car battery to the red/black crocodile clips on the 3-pin plug, to power abs ecu. Battery is a few months old, giving a measured direct reading of 12.45v
On the ph2 V6, I'm using the same switchable kkl set to 1/9, power to abs ecu is supplied by the car's electrical system. Battery is at least 4 years old, although when I tried got a reading of 12.35v on the battery.
I'm thinking, the obd socket on the V6 could be faulty, although I can connect to all the other ecu. Maybe not enough power is getting to the abs ecu for a stable connection. On a few occassions I've managed to connect to the abs ecu screen for a few second before it collapsing.
I might try and put a charger on the battery, and try to get voltage up to 12.6V, then try.